“Cryptojacking” has become a major security threat for PC users around the world.
The term refers to malicious software or scripts which secretly use your device’s resources to mine cryptocurrency.
These programs use your CPU or GPU to mine cryptocurrency and send it to an attacker’s wallet address, usually resulting in performance decreases on the victim’s machine.
Embedded cryptocurrency mining scripts in webpages could be a legitimate income source if visitors are consulted and notified of the script, but many perform this operation without the visitor’s consent.
Malware which runs cryptocurrency mining software is more malicious, as it aims to constantly drain a victim’s PC’s performance – even when no other programs are open.
Fortunately, there are several ways to combat cryptojacking scripts in webpages and malware.
If you visit a webpage and notice that your device is running slowly, open your task manager and check if your browser is consuming unusually high amounts of CPU or GPU processing power.
These hidden scripts use your device’s physical resources to mine cryptocurrency, and the effects of the programs are therefore relatively easy to spot.
You can also search the page’s HTML information for any references to “Coinhive” or other cryptojacking scripts.
To protect yourself from these scripts, you can install browser extensions which detect and block cryptojacking scripts on all websites.
These vary depending on the browser you use, but several popular add-ons are already being used globally.
Please note that using browser extensions carry their own risks, and they could block other elements on certain webpages.
Two popular anti-cryptojacking extensions, available on Chrome and Firefox, are:
It should also be noted that certain browsers like Opera have built-in cryptojacking protection software.
The installation of malicious cryptojacking software is more difficult to accomplish than the browser-based script scam, but has been a problem for a longer time.
If you have an effective anti-malware suite installed, you should be adequately protected against the most common cryptojacking malware.
However, if you are commonly downloading files from unverified sources and do not have additional protection, installing software such as Malwarebytes will help you combat cryptojacking malware.
Malwarebytes has also started blocking browser-based cryptocurrency miners, allowing users to install it as a catch-all solution.
In a statement regarding cryptojacking scripts, Malwarebytes said it does not regard the scripts as intrinsically malicious – but condemns their execution when user permission is not requested.
“The reason we block Coinhive is because there are site owners who do not ask for their users’ permission to start running CPU-gorging applications on their systems,” said Malwarebytes.